Encapsulation material

Chloriaated paraffias and modified types are used as solvents ia carbonless copyiag paper production based on the encapsulation of a solution of reactive dyes. Chloriaated paraffias fiiUfill the technical requirements for a solvent including excellent solvency for the dyes they do not react with the dyes nor encapsulation material, are immiscible with water, and have low volatihty and low odor. 

Eig. 7. Viscoelastic behavior of encapsulant materials (a) Newtonian fluid (b) non-Newtonian fluid. 

More advanced insulations are also under development. These insulations, sometimes called superinsulations, have R that exceed 20 fthh-°F/Btu-m. This can be accomplished with encapsulated fine powders in an evacuated space. Superinsulations have been used commercially in the walls of refrigerators and freezers. The encapsulating film, which is usually plastic film, metallized film, or a combination, provides a barrier to the inward diffusion of air and water that would result in loss of the vacuum. The effective life of such insulations depends on the effectiveness of the encapsulating material. A number of powders, including silica, milled perlite, and calcium silicate powder, have been used as filler in evacuated superinsulations. In general, the smaller the particle size, the more effective and durable the insulation packet. Evacuated multilayer reflective insulations have been used in space applications in past years. 

Kinjo, N., Ogata, M., Nishi, K. and Kaneda, A. Epoxy Molding Compounds as Encapsulation Materials for Microelectronic Devices. Vol. 88, pp. 1 —48. 

A final category of encapsulating materials consists of reaction products of the nucleus material and a reagent. For example, pellets of nitronium perchlorate have been encapsulated in shells of the less reactive amm perchlorate (AP) by exposing the pellets to ammonia gas. The fragile AP shells were usually further protected by a top-coating of A1 or a polymer film (Ref 2). The most familiar example of this process is the natural one wherein A1 powders (or articles) become coated with a protective coating of A1 oxide thru exposure to atmospheric air... 

Microcapsules can be used for mammalian cell culture and the controlled release of drugs, vaccines, antibiotics and hormones. To prevent the loss of encapsulated materials, the microcapsules should be coated with another polymer that forms a membrane at the bead surface. The most well-known system is the encapsulation of the alginate beads with poly-L-lysine. 

Sinclair, R. G., Slow-release pesticide system polymers of lactic and glycolic acids as ecologically beneficial, cost-effective encapsulating materials. Environ. Sci. Technol., 7, 955, 1973. 

A challenge in designing liposome systems is the assessment of drug release from such systems in vitro. Use of agarose gel matrices has been reported as one approach to evaluate the release kinetics of liposome-encapsulated materials in the presence of biological components [68],... 

Fig. 23 Saliva and serum IgA (primary and secondary) response following orally administered soluble antigen Streptococcus mutans cell wall extract (open circles, soluble antigen solid circles, liposome-encapsulated material) (phosphatidylcholine, phosphatidic acid, cholesterol). (From Ref. 277).

The interaction in an interface of device/tissue is limited by two factors. There is the corrosive environment, such as biological fluid, which contains salts and proteins among other cellular structures in which the sensor device must survive [47, 48], Second, there is the encapsulation material which may induce a toxic reaction due to poor biocompatibility and hemocompatibility [49, 50], It is crucial to use a biomaterial that can overcome both limiting factors to maintain the lifetime of the sensor device and protect the body [51, 52],... 

Another product has basically a built-in pH sensor. In this case the rinse aid is encapsulated into a material that is solid and insoluble in water at an alkaline pH-value. Thus it is able to withstand the conditions in the alkaline main wash cycle. When the pH-value decreases, due to the dilution of the washing liquor with pure water in the rinse cycles, the sensor encapsulation material becomes soluble and releases its contents [93, 94]. 

Plastic encapsulant materials (PEMs), in electronic materials packaging, 17 838-840... 

Cold cure silicone rubbers and available as pastes. These pastes are mixed with an organometallic catalyst and silicate and cured at room temperature. These are used as adhesives, and as encapsulating materials for electronic components. They are also used for textile coating and in moulds. 

For water-soluble agents, the encapsulation efficiency and thus the internal volume of vesicles which determines the amount of encapsulated material, is a very important factor with regard to the in vitro efficacy. It depends on the liposome size, lipid composition and lamellarity. When the number of liposomes delivered has to be known, the enumeration of the suspension can be performed by multinuclear NMR and photon correlation spectroscopy (110)-... 

EVA is a copolymer of ethylene with minor amounts (ca. 10 0%) of vinyl acetate. EVA has many uses as a foam rubber in everyday goods (like shoes etc.), as cable insulation and as encapsulation material in photovoltaic cells. 

Three classes of polymer encapsulant materials were studied. These are listed in Table I and Include novolac epoxy and silicone-epoxy compounds. A pure silicone formulation served as a control for comparison of the thermal degradion properties... 

There are two reasons why it is difficult to give examples of already marketed products based on encapsulation used in detergents or even household and consumer products. One is the fact that the technology is still not always applicable in a cost-effective way The other reason is that it is not always known that an encapsulated material is used, because companies like to keep the know-how in-house. Still some technologies are being used in daily life already [1, 2, 59]. 

The solvent precipitation technique is alto used to encapsulate material, ... 

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